


The Oncoming Safety Hazard

by evilqueenofgallifrey (MayFairy)



Category: Doctor Who, Ghostbusters (2016)
Genre: AU where Holtz is a Time Lord, F/F, and love each other a lot, and the others are her companions, it's just generally gay, replace ghosts with aliens and you have the same basic backstories, the romance will be kinda vague, they're all just generally gay for each other
Language: English
Status: In-Progress
Published: 2016-12-25
Updated: 2017-01-23
Packaged: 2018-09-12 01:26:46
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 2
Words: 7,855
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/9049636
Author URL: https://archiveofourown.org/users/MayFairy/pseuds/evilqueenofgallifrey
Summary: "Should I tell her? Is she gonna freak out?""Definitely.""Awesome." When Erin Gilbert was eight years old, she was visited by an alien every night for a year. Abby Yates was the only one who ever believed her, and the one who she knew would never forgive her for giving up on their dream. Erin has imagined countless times what it would be like to run into Abby again. She just never expected it to involve alien rhinos, bigger-on-the-inside wardrobes, or a mad blonde in goggles who just doesn't quite make sense.





	1. The Rhino, the Weirdo, and the Wardrobe

**Author's Note:**

  * For [answerstobefound](https://archiveofourown.org/users/answerstobefound/gifts).



> MERRY CHRISTMAS! This is the Christmas present for my darling Louise. It was supposed to be a oneshot but it got long and I haven't quite had the time to get it all done for posting in one go, so threeshot it seems to be! 
> 
> I hope this is everything you've anxiously waited for, Lou. 
> 
> (I'll confess I'm fairly worried about the characters, since it's my first time writing them and venturing into new fandoms always makes me nervous. Please feel free to give constructive feedback!)

Erin Gilbert has imagined countless times what it would be like to run into Abby Yates again. She just never expected it to involve alien rhinos, bigger-on-the-inside wardrobes, or a mad blonde in goggles who just doesn't quite make sense.

It had been a good six years for Erin. She has her Master's degree in theoretical particle physics and has been accepted into the PhD programme. And more importantly, she has put her mortifying obsession with aliens behind her - even if sometimes her study brings her a little too close to matters of space and the extra-terrestrial for comfort.

_You've just been watching too much X-Files._

_Alien girl._

_Freak._

The words never fade completely even if their impact is far from what it had once been. It's embarrassing to look back at what she had thought and done but painful as well because there is always that _what if_?

Which is why, when Erin walks right into Abby Yates on the streets of Manhattan, she has never been more blindsided in her life.

"Oh, I'm sorry, I-" Erin stops short when she sees who is in front of her. "Abby?"

"Erin?" Abby seems to be similarly bewildered and for several seconds they just stare at each other. They might have continued doing so for an insurmountable period of time if not for -

"Who's this?"

Erin tears her gaze away from her ex-best friend to notice for the first time the blonde standing at Abby's side. The other woman must be mid twenties, same as them, but there's something in her eyes that makes Erin a little less certain about that than she should be. Erin is used to seeing intelligence in people at first glance but this is something more. Not just intelligence but also _experience_ , more than is logical.

The blonde is wearing denim overalls with a strange circular design on the front pocket, over a dark green crop top. There are a pair of yellow tinted goggles atop her head which makes Erin wonder if she is a scientist like them or simply someone with a unique personal aesthetic.

"Erin Gilbert. My ex best friend," Abby says, with harsh emphasis on the 'ex' that makes Erin wince.

"M'kay, well, that's great, but we have...that thing," the blonde stranger says to Abby, "Kinda gotta get going. Soon. And by that I mean about three seconds ago."

"Wait, what is that?" Erin asks, for the first time noticing the bizarre device in the blonde's hands. It's about the size of a novel with a spinning disc on top, and looks homemade but also like it's doing _something_.

The blonde grins. "Morphic residue detector. Handy for finding shapeshifters who are, uh, getting around. Pretty neat, huh? Made it myself out of a toaster and a-"

"Sorry, did you say _shapeshifters_?" Erin asks, skeptically.

"Yep, following the trail of one that's been causing a real fuss around here - not his fault, he doesn't know how to act around 'the living dead'. We ran into him last night, managed to talk to him a bit, but he got scared off by-"

"The living dead? What does that mean?"

"Well, for his species, being unable to change shape is worse than being dead," the blonde says, like she's talking about a particularly interesting flower arrangement and not something that sounds utterly insane, "So naturally, humans are a little bit _really_ terrifying."

She has an odd, manic grin. It's unnerving.

"His species?" Erin is vaguely aware of the fact that she's mainly just staring at the blonde and repeating various tiny parts of her sentences with great confusion, but she doesn't know how to react. She's talking like - like - well, like _Erin_ used to, but it sounds _legitimate_.

"Don't bother, Holtz, Erin gave up on aliens a long time ago, she lives in a state of denial now," Abby says scathingly.

"Yeah?" Holtz - what kind of name is that, anyway? - gives Erin a once over, an easy smirk on her face. "Maybe she just hasn't met the right one yet."

Abby looks at Holtz with great exasperation. "No, we're not doing this now! You can flirt with every woman from here to Metabelius III and I don't give a rats ass, but you do _not_ flirt with Erin. Because Erin sucks. Now, we need to get going or we're never going to find Trien before that Judoon does."

"Yeeeeah, fair call," Holtz admits.

"What's a Judoon?" Erin asks, automatically.

"Alien rhino cop," Holtz answers without missing a beat, and just lifts an eyebrow when Erin snorts derisively. "Yikes, Abby's right about you. I don't have the time to work with this. Come on, Yates, we got a shapeshifter to save."

The device in her hands starts beeping and Holtz and Abby snap to attention.

"This way," Holtz says, and they start running back the way they had come.

Erin stares after them. They're insane, they can't _possibly_ actually be talking about real aliens, because aliens aren't real. But how could it be fake? Why would they lie, when Abby couldn't possibly have known that she would run into Erin? And that's the thing about Abby, she's always so...genuine. She says what she thinks and what she believes, and it seems to have gone from looking through a telescope and going over Roswell theories and talking about 'Erin's alien' to...whatever the hell Erin just witnessed.

Erin shuts her eyes for a moment, cursing herself, before running after them.

"Abby, wait!" She calls, and nearly busts a lung catching up to them. Since when is Abby _fast_? She'd never been slow, but she's downright speedy now.

"Get lost, Gilbert!" Abby yells over her shoulder. "I stopped needing you a long time ago!"

"In here," Holtz meanwhile says, coming to an abrupt stop, "It's a wax museum. Of fucking course it is. Brilliant. Literally, brilliant, Trien's got quite the little brain on him."

"Shapeshifter among wax figurines," Abby says, not sounding remotely thrilled, "Great. Just great."

Erin finally reaches them and is practically doubled over catching her breath. "But doesn't that device find him for you?"

"Not at this short a range. Morphic residue isn't like a tracking chip, it's _residue_ ," Holtz says, like she's stupid, and reaches out to run her finger along the door handle of the wax museum entrance. It comes away with a clear, sticky yellow substance coating the tip. "See?"

"Please don't-" Abby sighs when Holtz licks at the substance. "...do that."

"Mm. Tastes like earwax, with just a hint of lemon."

"I don't wanna know how you know what earwax tastes like."

"Live as long as I do, Abby, and play enough games of truth or dare in seedy spaceport bars, and you'll have a good seven dozen experiences you'd rather forget about entirely. But anyway, we were doing something, I was trying to make a point." Holtz frowns until a radiant smile lights up her face. "Oh, right, the residue. Tastes like fear too. Not that Trien being afraid is new, but this is _strong_. That aftertaste."

She reaches out to wipe her finger on Erin's white blouse, staining it with a truly hideous smear of yellow.

"Hey," Erin tries to protest, but Holtz just puts the finger to her lips.

"Is she going to go away?" She asks Abby.

"At this point? Probably not."

"Then I guess she's coming in."

Abby sighs, but upon glancing sideways stiffens at something she sees. "Shit, Holtz, it's the rhino guy, we gotta move."

Holtz grabs Erin by the hand and yanks her towards the door, giving her about half a second to glimpse the _bipedal rhino creature striding down the street in their direction_. Abby closes the door behind them and wastes no time barricading it with a bench.

"What was that thing?"

"Judoon, alien rhino cop, were you not listening?" Holtz asks, frowning at her and letting go of her hand to snap her fingers in front of Erin's face, making her blink. "Hmm. Slow reflexes."

"Holtz, forget about my annoying ex-best friend and focus on finding Trien!"

"Right," Holtz agrees, frowning at Erin before turning away to walk out of the entrance hall and into the main display room. "Trien! Trien, we know you're in here! The Judoon's outside, we don't have a lot of time. I can take you home, to your planet, but you've gotta trust me."

No response.

"How can you get him to his planet?" Erin asks.

Holtz gives her an odd look. "With my spaceship. Obviously."

As she moves off and keeps calling for Trien, Erin stops and takes a moment to try and process it all. Process that she's asking questions like she _believes_ all of this insanity. Like she isn't on the slipperiest slope for her sanity that she's been on since the matter of extraterrestrial life came up as a debate topic during her last year in undergrad. She'd had to leave the room.

And now she's possibly just seen an alien rhino cop – though that sentence alone is enough to make her want to check herself back into therapy – and is helping her old best friend and _her_ weird new friend look for an alien shapeshifter in wax museum.

"Wait," Erin says, very belatedly, " _Your_ spaceship? How could _you_ have a spaceship?"

"Work it out, Gilbert," Abby replies, rolling her eyes as she walks past her, "Holtz! You found him yet?"

No reply, but Erin is fairly sure she can make out the sound of voices in the next room. She and Abby creep in a few moments later, only to find Holtz standing there alone. She flashes them a smile that is just a little too friendly, a little too innocent. Erin would not have trusted it even if she hadn't seen Abby's look of scepticism beside her.

She feels breath on the back of her neck and whirls around only to shriek at the top of her lungs upon seeing her own face poking her tongue out at her.

"What the _fuck_?!" She exclaims.

Holtz bursts out laughing. "I'm sorry, I had to."

"What just-" Erin can only gape as the other Erin smirks at her and then _entirely shifts her physical form_ until she is actually a he, short and olive skinned with dark blue hair.

"Glad to see you're in one piece, Trien," Abby says, looking relieved and cracking a smile, "So I'm assuming if you two had time to plan this prank, we're all good?"

"He knows the plan," Holtz says, getting a new, smaller gizmo out of her overall pockets – which, now that Erin thinks about it, aren't big enough to fit the morphic residue detector on its own let alone this one as well.

"It's good to see you again too, Abby," Trien says politely but genuinely. A moment later, he and Erin can't help but wince at the sound of the wax museum's front door cracking under the force of the pounding it is taking from the Judoon.

"So, you have a plan?" Erin asks.

Abby grins. "She always has a plan."

"Or at least, you know, part of a plan," Holtz says, her fingers flying across the buttons of the smaller gizmo, "Or something that _could_ be a plan." She looks up and grins proudly. "Or I'll – I'll just do something, hope for the best, and say afterwards that it was part of the plan."

"But it's not."

Holtz grins. "Almost never."

"That is far from reassuring," Trien says to her nervously, his voice thickly accented in a way not dissimilar to Russian.

"Agreed," Erin says.

"If you worry-warts could just give me a second," Holtz says, her tongue sticking out of the corner of her mouth as she keeps fiddling with her gizmo, "Our ride will be here very very soon."

The smashing of wood makes Erin jump, and heavy footsteps start heading in their direction.

"Holtz, the Judoon," Abby says urgently, "Are you sure the remote control works? We haven't tested it yet-"

"Wait, we're relying on something that hasn't been _tested_?!" Erin yelps, as she runs to slam the door shut in the hopes of buying them a few more precious seconds from the rhino cop she glimpses before she locks it.

"Just hang on!" Holtz retorts. A moment later, a wheezing sound not unlike the groaning of machinery fills the room and she and Abby visibly relax as a shape starts to form in the air between them.

"Is that…a wardrobe?" Erin asks with bewilderment.

"Yeah, we landed in a furniture store," Holtz says, shrugging as she takes out her singular earring to shove the key dangling from it into the lock that doesn't quite fit with the rest of the wardrobe's design, "Alright, everybody in!"

Trien looks dubious, but Abby reaches out to take his hand and he allows her to gently lead him inside. It seems she hasn't lost that quality in her that can make anyone follow her lead.

"But, we're not all gonna fit," Erin stammers, just as the door opens open and a rather furious space rhino storms in.

"No time for that," Holtz says, grabbing her by the shoulders and physically shoving her through the wardrobe doors. "Sorry, Captain, no arrests today. I'll be giving Mr Trien a nice ride home free of charge. You're welcome. Say hi to your boss for me. Catch ya later!"

Erin is so busy being amazed at her cavalier attitude that it is only just then that she turns around and realises that she is standing inside a large room, not the inside of a wardrobe.

"I…. _what_?"

The room feels like the lair of a mad scientist from a cartoon. The entire space is dominated by a large hexagonal console with a central rotor that extends all the way to the ceiling. The console is a mess of wires and lights and what looks like a vintage typewriter wired into the system alongside some tech that Erin has never laid eyes on before. It all looks like it could fall to pieces with the wrong touch.

"Pretty sweet, huh?" Holtz says from beside her, clapping her on the shoulder. "It was Erin, right? Erin, welcome to my TARDIS and aforementioned spaceship."

"But-" Erin's head is spinning. "A wardrobe can't be a spaceship."

Holtz is grinning. "Says who?"

Erin is sure she has a good answer for that, somewhere, but comes up short because _it's bigger on the inside and oh yes there was that feeling of spatial disturbance as I stepped over the threshold which implies interdimensional transference but this shouldn't actually be possible –_

"Besides, it's not actually a wardrobe," Abby says from where she is checking a screen attached to the console, "The wardrobe is just a disguise. Obviously."

"Obviously," Erin mimicks with annoyance, "Well I'm sorry, Abby, if my difficulty to take in all of this _absolute insanity_ isn't impressive enough for you."

"Eh, you're doing fine," Holtz says, giving her a playful punch to the shoulder, "But you know what _is_ impressive? Me. Or rather, what I just did. I mean, did you even _see_ that?"

She moves towards the console and stands in front of Abby, her whole body bouncing with manic energy while Abby just looks on with fond amusement.

"Abby. Abby, Abby, Abby." Her hands are planted on Abby's shoulders while her feet and lower body move in a kind of Elvis mimicry. "The remote control _worked_!"

Abby chuckles. "You kept saying it would. I only had a single second of doubt, I promise."

Holtz holds up the remote control as she looks back to Erin. "Stole it from a _really_ salty biochemist back home. God, she hated me." She shakes her head and chuckles. "Of course, she hated everyone, and no one really liked me, so we actually got on pretty well, considering."

The other three just stare at her and she makes a face.

"Anyway," she says awkwardly, before breaking out into another grin, "Time to get you home, Trien! One solidly economy class seat back to Lorra coming up. Well, it would be if we had a seat, which we don't. Abby, you know the drill."

Holtz starts moving around the console, her hands travelling over the ramshackle controls with an ease and dexterity that makes it impossible for Erin to look away. Abby moves in a slower counterpoint, just pressing things here and there, her lack of speed and frown of concentration the only things that betray her lower level of confidence.

The ship starts to shake and Erin has to grab onto the door handle to avoid falling on her face, while Trien is not so lucky. Abby and Holtz are clutching the console and the latter lets out an enthusiastic whoop.

The wheezing that had signalled the ship's arrival in the wax museum fills the room again now, and then the shaking finally stops.

"Is it like that every time?" Erin asks, when she can finally find her footing again.

"Not _every_ time," Abby replies in the same moment that Holtz says, "Damn right. I love it."

It occurs to Erin that there's a chance she could be dreaming. It's strange to think it's taken this long for this incredibly strong possibility to have occurred to her, and she wants to believe it, since she has always had such an imagination that shapeshifters and alien rhinos aren't much of a stretch.

She's not sure, however, that she could have thought up somebody as odd as Holtz or her weird bigger-on-the-inside wardrobe.

"Thank you for all your help," Trien says to Abby and Holtz gratefully as they head back towards Erin and the door, "I owe you my freedom. Possibly my life."

"Happy to help, buddy, it's not your fault you got caught up in that rift storm and ended up in New York of all urban jungles," Holtz tells him cheerfully, before her face and posture become more awkward. "Just, uh, now that you're home, do me a favour and get your family packed up. Go somewhere else. Emigrate. Just as a general, uh, tip from someone who may or may not know that your planet is going to have a minor…invasion, next year. Best to just...not be around when that happens." She taps her nose.

Trien stares at her for a moment. "I – alright. I'll keep that in mind. Thank you, Lady Holtz."

Abby struggles to smother a giggle and Holtz snorts but just opens the doors and spreads her arms. "Like I say, happy to help. Now get back out there and do your thing. Shift. Flow. Whatever you call it."

"I will," he said, and steps out onto a rocky landscape overshadowed by a deep violent sky.

Erin's eyes widen. "Is that-"

The door is slammed shut before Erin can work out exactly how she wants to word her question, and she doesn't get a chance to express her annoyance because Abby and Holtz have burst into laughter so powerful that there are tears in their eyes.

"He called you – Lady Holtz!" Abby manages to get out, clutching her gut.

Holtz half wheezes with laughter. "I know, I know, you tell people you're a Time Lady and some of them just fucking run with it. Like, okay, sure, it's _technically_ an accurate form of address, but have you seen me? Who looks at me and goes 'oh yeah, that's a real _lady_ '?"

"Sorry, Time Lady?" Erin asks, weakly.

Holtz glances at Abby. "Should I tell her? Is she going to freak out?"

"Definitely."

The blonde cackles. "Awesome." She regards Erin with a small smirk. "You, Miss Erin Gilberry or whatever your name is, have the esteemed honour of addressing one of the only surviving Time Lords of Gallifrey, a horrifically pompous and boring planet on the other side of the universe that no longer exists."

She does a huge, sweeping bow, but one that is obviously intended to be silly given that she wiggles her bum a bit before straightening back up and slinging her arm around Abby's shoulders.

"And Abby here is my wonderful companion/partner in crime," she says happily, squeezing her hard, "Not actual crime, mind." She laughs. "Though that can happen too. Hazards of the job. Abby's the first human I've met who could handle it. First two humans I tried didn't really work out. Your species can be…so dumb. Like wow. Really. Wow."

"To be fair, from what you've told me about Kevin, he really was an outlier even by human standards," Abby says.

Erin can't really hear them anymore. She heard _humans_ and _your species_ and _horrifically pompous and boring planet on the other side of the universe_ and what that means about Holtz is just too much. It's all starting to sink in now, everything she has tried to shut out for years now screaming at her to face it, the aliens and the bigger on the inside spaceship. And it can't be real, it can't be, but it's so vivid and she's wants to be sure she couldn't make any of this up but that's what she'd thought about the Star Poet too –

_Erin, honey, you don't have to make up stories to get attention –_

_Erin, do you want to tell me about why you tell your parents that an alien comes to visit you at night? You know that lying to your parents isn't good? Or are you hearing voices, telling you they're an alien? Do you think it's possible it could all be inside your head?_

"Oh shit, she's having a panic attack," Abby says. Her voice sounds so far away to Erin, like it's through water or honey or a wall.

"Oh crap."

Hands – Abby's hands, as soft as Erin remembers – cup her face and force her to look away from the wall.

She thinks she hears her name being said, but her chest feels hot and she can't _think_ because this can't be real, none of it, it was never real, she was just crazy, except she's not and she never has been, she _saw_ that alien, talked to it, he had been real and a part of her had never stopped believing.

It isn't until a familiar tune fills her ears that she starts being able to breathe again. _Hooked on a Feeling_ isn't her favourite song by far and Abby's voice is nothing spectacular but suddenly it's like she's seventeen again and on her bed, Abby's arms around her and her voice soothing the panic away. Why this song? They had no idea, it became the remedy for any kind of awful feeling either of them had, no matter what.

And she had had no idea how much she had missed it until this moment. As Erin's heart rate comes back down, all she can do is stare at Abby.

"You remembered," she whispers, and Abby smiles, her thumb stroking her cheek.

"Yeah, of course I did, you dummy."

"So….aliens," Erin says, very quietly, with a shaky, hesitant smile, "Aliens are…real. Really real. Actually….real."

"That's me, really actually real," Holtz chimes in, beaming.

Abby, for the first time all day, only has eyes for Erin. She just smiles and wipes the tears from Erin's cheeks with her thumb. "Yeah. They're real, Erin. We were right. You were right. You always were."

"I'm sorry for leaving and saying all those things," Erin says, swallowing.

"We both said some awful stuff, let's forget about it."

"…friends?"

"You bet."

Erin lets out a tiny sob of relief and then they're hugging and she feels whole again for the first time in years, like she hadn't even realised that a part of her was missing until it was back in her arms.

"Aw," Holtz says from behind them, wiping a tear from her eye that may or may not have been imaginary and shaking her head. "You kids are so sweet. Glad me and the old boy could help."

Erin lets go of Abby to regard Holtz with new awe, hand over her mouth.

"You're an alien."

"Yep."

"With a spaceship."

"Yep."

"Oh my god, no, Erin, that's not even the best part!" Abby exclaims, making Erin blink at her. "Erin, it's not just a spaceship – it's a _time machine_."

"...what?"

"TARDIS," Holtz says, grinning, "Time And Relative Dimensions In Space. That's what this thing is. My TARDIS." She pats the wall fondly. "I call him Bob. You want a tour?"

"I – _of course_ I want a tour of your alien time machine spaceship," Erin stammers, laughing at her own words, "Oh my god. This is actually real."

"You better believe it, baby," Holtz says, "And any friend of Abby's is a friend of mine – well, any cute friend of Abby's with a passionate interest in aliens, anyway. So, you can stay as long as you like."

"You mean, she can come with us?" Abby asks, face lighting up.

"Uh, yeah. I mean, I don't know how smart she is, but we can always just work around-"

Erin coughs. "I actually just got my Master's degree in Theoretical Particle Physics," she says, "So I think I'll be able to keep up."

Holtz's eyebrows lift. "A human physics degree. Cute." Erin tries and fails to not be offended, and it must show on her face because Holtz laughs and punches her on the arm. "Ha, I'm kidding! Well, half kidding, but really, it's way better than what I was expecting. You'll do nicely, Gilberry."

"Gilbert."

"Oh. Really?"

"Yeah."

Holtz looks disappointed, but only for a moment. "Ah well. You can still stay."


	2. The Time Machine

**Summary for the Chapter:**

> Erin gets a tour of the TARDIS, and a bit more of an insight into its owner.

**Notes for the Chapter:**

> HAPPY BIRTHDAY LOU! 
> 
> I'm sorry it's taking me so long to get this done, but BBC Class (or rather, Quill specifically) owns my gay ass at the moment. But I made sure to get this done on time. I actually nearly posted it a day early WHOOPS timezones :P 
> 
> Enjoy!

The Time Lord - Time Lady? - spreads her arms and looks around the room with pride. "So this is the console room. The main event. All that jazz. For now I'm gonna say….don't touch anything. Because pressing the wrong button could result in an implosion of this ship and half a galaxy with it so let's, uh, avoid that."

"Couldn't you just...label those buttons? With little warnings?" Erin asks weakly.

Holtz snorts. "Warning labels are for dudes. And humans."

"...right."

"And now, the pole," Abby says to Holtz, who grabs Erin by the hand to pull her to a spot near the console where a pole disappears into a hole in the floor.

"Is that…a fireman's pole?"

"Yep."

"How did you even get that in here? Did you steal it?"

Holtz chuckles. "Surprisingly, no," she says, pointing her finger upwards. "Good old Bob here can make almost anything for the rooms, with the right specs. Now follow me."

She slides down the pole, and after a glance at Abby, who nods, Erin follows her. They are now standing in a rectangular room even larger than the one upstairs, the back of which is the exact kind of crazy science lab that the décor upstairs had led Erin to half expect, and the front of which is the comfiest looking living space Erin has ever seen. Squishy couches and cushions and beanbags and an outrageously large television screen on the wall.

"This is amazing," Erin says, awed.

"Damn right it is, and just through this door here is basically anything else you could possibly want. Bathroom, bedrooms, pool, exercise room-"

"You deleted the exercise room to give us some extra thrust when we were running away from those Rutans last week," Abby says without looking up from her phone.

"Oh yeah," Holtz says, snorting, "Well, what would we use an exercise room for, anyway? Like we don't do enough running as it is."

"I noticed that actually," Erin says to Abby, "You can _run_ now."

"Job requirement," Abby replies, sighing, "You'll get there too, if you're gonna be staying. So what do you think?"

"Stay here? And be, what did you call it? A companion?"

"I mean, the title isn't super important, I totally stole it from this other guy," Holtz says, flapping her hand. "Travelling companion just more or less covers the basic job description. I always thought 'assistant' sounded kind of patronising."

"So I could be an alien's travelling companion, with my best friend, and all I have to do is stay in this time travelling spaceship?"

"Pretty much," Holtz says. "Interested?"

"Oh, and before you say anything about your course, remember that it's a time machine, so she can get you back for ten minutes after you left," Abby points out.

Erin lets out a long breath. "Well then, I guess…how could I say no?"

"Yes!" Holtz punches the air. " _Two_ companions. This is like Christmas." She hugs Erin, tightly, much to the human's alarm. It's stiff and awkward, like Holtz doesn't quite know how to do it but is doing it because she feels like she should.

Erin gives her a tentative smile when she pulls away, and Holtz looks reassured, her grin back as her hands go to her pockets and she rocks back on her heels.

"Okay, well, you go and find yourself a room, Abby can help you. Should be something workable that you don't hate. I'll get to recalibrating the atom accelerator, and then you guys can let me know where you wanna go next."

The Time Lord runs off towards the ladder on the other side of the room which goes up through the ceiling and back to the console room, leaving Erin and Abby alone.

"Where did you _meet_ her?" Erin asks, after several seconds of silence.

Abby grins. "Spotted a spaceship coming down one night, about a year ago. Went out to have a look at the wreckage, and there was Holtz, digging around and licking things and talking to herself. I started asking questions and she just kind of answered them without looking up, without really thinking." She cackles. "Took her a full two and a half minutes to realise I was there and that she'd been talking to someone."

"And then, what, you two just teamed up?"

"Well, she said it never hurt to have another pair of hands when dealing with an alien lizard with seven, and that kind of logic is...difficult to argue with," Abby says, shrugging.

"Well, uh, yeah, I suppose it is," Erin replies, smiling uncertainly. "And then what?"

"Then when the lizard stuff was over and done with, she asked if I wanted to come with her. See more planets and aliens, help her out with all the crazy stuff she gets up to."

"And you, being Abby Yates, the girl who has seen every episode of _The X Files_ four times and who got sent home from school five times for yelling about aliens to the teachers, didn't even hesitate," Erin guesses, grinning.

Abby grins back. "Not even for a second. It's like a dream come true, Erin, it really is." She clasps Erin's shoulder. "But something was always missing. I tried to ignore it, but… I guess I always knew… it was you. All of this is great, Holtz is great, but you're my best friend, Erin. Doing this without you always felt a bit wrong."

Erin feels herself tearing up. "I'm sorry for being such a - I don't know-"

"Asshat?" Abby supplies helpfully, making Erin laugh and nod.

"Yeah, asshat, let's go with that. I'm _so_ sorry, I just couldn't take it anymore, the way they all laughed at me-"

"Don't worry about it. Think about it, if we hadn't had that fight, who knows where we would have ended up? I might never have seen that spaceship, and never met Holtz, and then where would we be?" Abby smiles at her. "Now, you get to be here and know that they were all _wrong_."

Erin wipes at her eyes and nods again. "This place is… incredible. It shouldn't even be possible."

"She calls it transdimensional engineering. I'm sure if you asked, she could try and explain it to you. I don't know if you'd understand, but you'd have a better shot than me. Now come on, let's find you a room."

Abby pulls her into the corridor, and they pass rooms marked 'Holtz' and 'Abby' until they come across one that says 'Erin'.

"Oh hey, he's already made you one," Abby says, clapping her hands together. "Nice."

"But… how?"

"The ship's kinda alive," Abby explains, and laughs at the alarmed look on Erin's face. "I know, bit freaky, but you get used to it. He's telepathic, so this room will be you down to a T, I bet."

Sure enough, Erin pushes the door open and walks into a room that couldn't be more _her_ if she had designed it herself. The bed and its linen are basic, the duvet cover a nice calming yellow against the plain white walls. There's a fireplace with a bookshelf of physics books on the mantle, and a comfy armchair next to it. An ugly knitted blanket rests on the end of the bed, identical to the one that her grandmother knitted her for her tenth birthday, the one she has kept with her all her life but now sits in her little apartment.

Erin feels herself tearing up. "This is...I don't even have words."

"I know," Abby says, rubbing her back, "Look, I'll leave you to get settled, give you some time to get your head around all this, cause I know it's _a lot_. I'll just be out in the living space, okay?"

"Okay, thanks," Erin says, and she takes deep breaths as Abby shuts the door behind her.

She sits on the bed and tries to let everything wash over her. She's in a spaceship. With an alien, and Abby Yates, who is now her best friend again like nothing ever happened because _aliens are real and they've always been real and Erin was always, always right_. She was never crazy. Her parents and the therapists were wrong.

Her hands reach out for the knitted blanket and instantly she can feel herself calming down, her heart rate slowing. It even _smells_ the same. How is that possible?

"Abby said you were telepathic," Erin says, looking at the ceiling which is covered in glow-in-the-dark stars like her childhood bedroom. "So I guess that means you pulled the smell from my memories, huh?"

The room lets out a tiny hum which sounds oddly like a 'yes', making Erin jump a mile.

"Okay, sentient spaceship, that's gonna take a while to get used to," she mutters to herself, "but uh, thanks, I guess. For the room. It's perfect."

The fire roars to life out of nowhere, and Erin takes that to mean 'you're welcome'. She leafs through a few of the physics books and takes comfort in the familiar formulas. Some of the ones to the right don't look like they're from Earth, and that's intriguing, but she thinks it's been a big enough day without looking into alien physics. There will be time.

She has all the time in the world. It's….. an incredibly comforting thought, actually. The idea that she currently exists in a space that is outside of her usual world and time. So long as she can go back for five minutes after she left, the TARDIS is a safe haven away from the life that has brought her nothing but anxiety. (Sure, it has its joys, like physics and ice cream and cats, but those only go so far.)

Finally, she feels calm enough to leave the room and the blanket behind and go to find Abby.

Problem is, that when she comes out into the living space, Abby is slumped on the sofa, glasses skewed and fast asleep. Erin feels put out for a moment, her one familiar element currently unavailable to her, but Abby looks so sweet and so exhausted that she grabs a blanket from the large pile nearby - Holtz really knows how to stock a living space - and drapes it over Abby, removing her glasses and putting them on the coffee table.

"Oh, so _that's_ what I should be doing when I find her like this," a voice says from behind Erin, making her jump, "I knew I was missing something really obvious."

Erin whips around to see Holtz standing there with her hands in her pockets and a sheepish look on her face.

"Does this...happen a lot?"

"Yeah…" Holtz shakes her head. "She tries to keep up with me, no matter how much I tell her she can't. You know what she's like, stubborn as a three headed mule. But she's only human, and eventually the batteries need recharging."

Erin tries to work out what she means. "So your batteries need… less recharging?"

"Yep," Holtz says cheerfully, "I can basically survive on ninety minute power naps. Or I'll just go a whole week without sleep and get a solid seven hours and then I'm good to go for another nine days, minimum."

"So your species, you said _Time Lord_? Is that right?"

"It's complicated, all this stuff to do with titles and academies and Gallifreyan versus Time Lord but yeah, in a nutshell, that's me," Holtz says, shrugging, "Time Lady works too, but I'm not picky."

"Right," Erin says.

"Wanna see something awesome?" Holtz asks with a grin.

"Uh, yes?"

"Jeez, no need to jump on me with all that enthusiasm, Gilbert," Holtz says, whistling.

"I do," Erin says more eagerly, "I do want to see something awesome."

"That's more like it." Holtz looks pleased. "In that case, follow me." She heads for the ladder up to the console room and Erin follows her back up.

It's strange, being alone with Holtz, whose internal energy can be felt even if one is standing several feet away. Which she's not, because Holtz is right up in her personal space. Maybe Gallifrey doesn't have issues with it, but Erin has a sneaking suspicion it's more to do with Holtz herself than her people.

"Okay okay okay," the blonde says excitedly, "Close your eyes."

"Why?"

"Just trust me, okay?"

"You're an alien I met like an hour ago, trusting you would be probably the most illogical thing I could do in my entire life."

Holtz's eyes are amused and knowing. "But… you do. Right?"

Erin is shocked to realise that she does. There's something about this mad, bizarre alien woman that is just so inherently genuine. For all her joking and pranking, there's not a bad bone in her body - of that Erin is certain.

Erin swallows, nods, and shuts her eyes. Holtz takes her hand and leads her forward.

"Okay. Open."

Erin does, and finds herself standing at the open doors of the ship, staring out over the earth from above. The entire world before her, the country she was born in and the land that she has walked laid out like it's tiny and not the only thing she's ever known.

"Oh my god," she breathes.

Holtz is leaning against the doorframe, grinning. "Not a bad view, huh? Makes my top five, easily."

"What are the other four?" She asks, a little absently.

"All in good time, Gilbert, all in good time," she says, patting Erin on the back. "Now, are you hungry?" When Erin looks at her with confusion, she just laughs and pulls a packet out of her overall pocket - again, one just a bit too big to plausibly fit in there.

"Okay, seriously, how do you keep doing that?"

"Doing what?"

"Pulling out things that can't _physically_ fit in there!" Erin awkwardly gestures in the direction of the pocket with her hands.

"Oh," Holtz laughs, "same trick as the spaceship. Transdimensional engineering - bigger on the inside."

Erin stares at her for a second. "Well, _obviously_!" She says, making Holtz blink at her with surprise. "Even if Abby hadn't mentioned it, I'd have known because I felt that spatial disturbance on my way in, and okay, I was a bit busy freaking out and kind of still am, but interdimensional transference isn't exactly a _difficult_ leap to make, especially since I know you're an alien with obviously more advanced technology. I might not understand exactly how it works, but that's not actually the part I care about right now."

Holtz looks utterly blown away, eyebrows nearly at her hairline. "Okay…. so, what part _do_ you care about?"

"From all of that," Erin says, a little breathlessly, pointing her finger at her, "I have to conclude that you have another dimension, in your pocket."

"Well, yeah. So?"

"So, doesn't that strike you as, well, _ridiculous_?"

Holtz starts laughing. And doesn't stop. She laughs and laughs and laughs while Erin just watches, bemused and wondering what to do.

Finally, Holtz straightens up, tears in her eyes, and grabs Erin by the shoulder. "I knew I liked you, Gilbert."

"Really?" Erin asks. She's been liked by so few people in her life that it's very difficult to imagine that anyone could take to her so quickly. But then, she's always been called weird, and if Holtz is anything, it's that. "Why?"

"Who cares about why? I don't know why. I just know who. Which is Abby, and you."

Erin feels inexplicably touched, and when Holtz sits down so that her feet dangle out over the edge, Erin only hesitates for a second before following suit. Their legs swing out in the emptiness of space.

"Okay, so I probably should have asked this before, but how are we breathing?" She asks.

"The TARDIS extends the oxygen shell, easy peasy lemon squeezy," Holtz says, before snorting. "Okay seriously, who came up with that phrase? Your species has the most incredible capacity for creating total nonsense, and I _love it_. I mean, that cat who looks like a poptart shitting a rainbow with the most epically annoying music playing over and over? Amazing."

"Uh, thanks?" Erin asks, finding herself laughing a little.

Holtz opens the packet she's been holding and holds it out to Erin. "Chocolate?"

Neither the packet or the round thing Holtz pulls out looks like anything that Erin has ever seen before, but it seems rude to say no, so Erin takes two and puts them in her mouth.

It's not like any chocolate she's had before, it's richer and filled with something a bit like jam with a flavour somewhere between orange and strawberry.

"Oh my god," Erin says, with her mouth full, covering her mouth when she realises she has done so.

Holtz beams. "Oh yeah, there you go. They're from this tiny human colony about three galaxies over and four centuries ahead of your time."

"They're amazing."

"Well, have as many as you like."

They sit there in silence for a while, eating the chocolates and gazing out at the earth below them. Erin's head has quietened, the numerous questions blurring together into a white noise she can ignore for the moment.

Instead she looks at Holtz, who is leaning back on her palms which are planted behind her, legs still swinging in the open space. It's the first time Erin has seen her quiet - still is something she seems to be incapable of, but quiet… perhaps sometimes.

She still looks so _human_.

"Wait, so is this what you actually look like?" Erin asks suddenly. "Or is that like a suit or a hologram or something so that you can move around Earth without freaking humans out?"

Holtz laughs. "Nope, this is what I look like. Convergent evolution, you know."

"Oh, right."

"My insides would give your sciences a migraine, though," she says, grinning. "The binary vascular system is the least crazy thing I've got going."

"Binary vascular - you've got two hearts?"

"Yep. You wanna listen?"

"No, I'll believe you. Maybe another time, though." Erin thinks about how she ended up here, having this conversation. "So, how you said Trien got caught up in a rift storm, and that's how he ended up in New York. Could you….explain that?"

Holtz nods eagerly. "Basically, all through the universe you get these little rifts in time and space. Like tears, where things can fall through from one place and time to another. New York has a little one, easily managed so I tend to keep an eye on it. Old Bob's got a permanent subroutine monitoring it so I get told if anything big pops through it. Now Cardiff, that's a _huge_ one, I stay well away from that."

"Why? Wouldn't that need even more help? Be even more dangerous?"

Holtz's grin is fixed in place. "They got a guy. It's fine."

"A guy? What, someone like you?"

"Baby, there's no one like me," Holtz says, winking, and Erin has to laugh at that. "But uh, yeah, same species. Saving worlds and fighting monsters is kind of his thing, so I let him do that. I'll help out people if I can but mostly I'm in it for the thrills and the fun and the pretty girls. Besides, if I get too involved in anything I might run into him, and we _really_ don't want that."

"Why not?" Erin asks.

"Well, then he'd know I was _alive_. And then he'd want to like, hang out."

"Why?"

"Well like I said, our planet's gone. Last of our species. So if he found out that he isn't the only one left, he'd get all clingy and want to hang out all the time. Or worse, travel together. Who knows."

"What would be wrong with that?"

Holtz pulls a face. "He's a total downer. And king of melodrama. And I'm _so_ not about that. Nope, he can hang out with _his_ human friends, and I'll hang out with mine. No need for him to ever know I'm alive."

"That seems kinda harsh. Not letting him know you're alive."

"I mean, I'm like 80% sure he's the reason our planet doesn't exist anymore, so my guilt level is pretty much zero," Holtz says, shrugging.

"Oh. What happened?"

"There was a war. Everyone lost, I guess. I dunno," Holtz says quietly, not quite looking Erin in the eye. "My mentor, Gorin, she got me out just before shit _really_ hit the fan. I wanted to stay and kick some more Dalek ass, but she wouldn't take no for an answer. I guess she saved my life."

There's a deep sadness in Holtz's eyes now, and Erin shifts her hand so it's resting over Holtz's, and the blonde blinks and then smiles at her in that uncertain but soft way of hers.

"Yeah, well, anyway," she says awkwardly, "point is that I'm alive and still rocking, and the Doc would kill my vibe, so I'm keeping well out of his way. I just want to kick back with my gals and have some fun, you know?"

"Sounds fair to me," Erin says.

"Exactly. Now, what do you say to helping me make some repairs to Bob while we wait for Abby to wake up from her nap? And then - alien planet time."

It sounds incredible, and so Erin says as much. Holtz grins and gets to her feet, offering her a hand up, and they get to work.

**Notes for the Chapter:**

> Thanks for reading, let me know what you thought!


End file.
